Many victims are also tricked into handing over details of their bank accounts and other personal information to the criminals, who then raid their accounts or make financial transactions using those stolen details.

Image:Rochelle ended up with a blocked bank card

Dan, from north London, has been scamming social media users for several years.

"They want to make easy money. They just think they're handing over a bank card with their details," he said.

"They don't realise they're not going to see any of this money at the end of it."

Dan said neither he nor any of his friends carrying out similar scams have ever been caught.

He said online media companies and the police never seem interested in pursuing offenders.

Across the internet, particularly on social media, temptation is everywhere. These are glamorous looking accounts offering get-rich-quick schemes.

The ads claim "it's easy money" and according to Dan there is no shortage of people, particularly the young, willing to take the risk.

"The easiest way now is to go on Instagram and type in 'instant cash' or something like that," he said

"There's so many following these groups, advertising the exact same thing you are. There are thousands who want to get rich.

"You just drop them a line saying 'do you want to make easy cash? - have you got a card?' and you're quickly inundated with lots of takers."

Image:Social media apps are being used to target young people

Dan's assertion is borne out by the latest figures from leading fraud prevention agency Cifas.

They show that between January and October last year, around 30,000 money mules were identified in the UK - around a third were aged under 21 and almost 5,000 were younger than 18.

Rochelle was just 15 when she was approached on Instagram and offered the chance to become a money mule.

As a young teenager, she had no money and the offer of a few hundred pounds for sharing her bank details seemed too good to resist.

But it was scam. Money was laundered through her account, but quickly withdrawn again and she got nothing from the criminal gang.

The bank later questioned her and blocked her account.

"I felt really humiliated, because I can't believe I actually thought that I was going to get this money," she said.

"I think people are actually afraid to say that it hasn't worked, because they feel humiliated and embarrassed.

Social media companies have been accused of doing little to stop criminals exploiting their networks.

Image:Fraudsters are using Instagram and Snapchat to scam people out of money

Instagram said: "Criminal activity is not allowed on Instagram and our community guidelines clearly state that people must follow the law. We encourage people to report content they think is against our guidelines using our in-app tools."

UK banks are being more proactive, joining forces and using sophisticated computer algorithms to pin-point fraudulent activity.

Tony Blake, head of fraud prevention for UK Finance, said: "The ultimate aim is to stop the money going in, to freeze that money and hopefully repatriate it, if possible.

"We obviously also want to close those accounts and stop those people opening accounts in the first place."

The police have told Sky News they will pursue those involved in trying to launder money through the banking network.

In October 2018, Michael Lanyuru, 24, from east London, was jailed for 21 months for laundering cash through money mules.

Acting detective inspector Paul Curtis, from the financial investigation unit at the City of London Police, urged social media users to adopt a common sense approach when faced with tempting online offers.

"Ultimately, there is no free money. If somebody is asking to use your account for a fee, that is illegal.

"You have to make sure you know where the money is coming from and if you can't account for it, you do risk prosecution for money laundering."

Fraudster Dan said he believes the risk of being caught is negligible and he plans to keep on committing online crime as long as there are willing victims.

"If you keep going online and you keep seeing these accounts with 7,000 people on it.. that's like 7,000 potential people that would willingly hand over their bank card. Once they hand over their bank card, that's it."